In ATK, the flash size will only be shown after a successful operation involving the flash.

I've checked carefully and noticed the following:
- my device drops out of USB downloader mode very soon when there is no USB cable connection to my PC
- my device also drops out of USB downloader mode very soon when no communication is happening between the PC and the device. I guess that should be done by a properly installed USB driver, but I'm not sure about that yet.

In ATK, the flash size will only be shown after a successful operation involving the flash.

I've checked carefully and noticed the following:
- my device drops out of USB downloader mode very soon when there is no USB cable connection to my PC
- my device also drops out of USB downloader mode very soon when no communication is happening between the PC and the device. I guess that should be done by a properly installed USB driver, but I'm not sure about that yet.

weird...ATK showed me the flash size in the working one from the beginning, even before pressing the dump key.
Did a little playing around with entering the download mode, easiest thing was to open the device manager, hold the power button, wait till the iMX35 disappears then press vol -, release the power button and a second later the vol -.

Tried it on the broken one, seemd to work but was not able to load the kernel into ram, allways failed to write to flash.
Connection got reset on a second try, which accorrding to the iMX35 manual is normal, the watchdogtimer checks the function and blocks after 32 seconds, another reset is needed after that.
Also explains why it drops out if no connection is there.

But my final diagnosis on my bricked one...its a paper weight.
Charged the battery in the working one, it worked flawlessly in there and swapping it back made no difference.
Absolutely no output on the serial port.
Not beeing able to dump, program or erase even though I was pretty sure about beeing in download mode probably means the memory is fried.

Would have liked to contribute a bit more, but playing around with my girls K3 seems a bit too risky, especially because she needs it for our holidays starting saturday.
The USB download mode is surely the best solution, enables a "fire and forget" option and is way less cost intensive and complicated then the serial upload.

Will join the libusb tryouts as soon as I get my own working K3 (probably end of August) and as soon as a working Win7 solution is available ;D
Only problem I see would be how a noob could get the .bins from the .img files.

The Vol- button might be pressed the whole time, it does not matter if it is ever released, it just has to be pressed upon K3 reset. As I said before, I think I'd just tape it down when timing is unclear.

It also seems I had installed two drivers that came with ATK: the MX35 one plus the "windriver", by running "wd_install_4NT.bat". Not sure if both are needed, but I think the latter might provide functions for the other one.

I would certainly not risk a K3 that is "in production use" and not broken :-)

The Vol- button might be pressed the whole time, it does not matter if it is ever released, it just has to be pressed upon K3 reset. As I said before, I think I'd just tape it down when timing is unclear.
...

I do not press my "magic key" until just before releasing the power button. The only requirement is that the "magic key" (Vol- on a K3) be down when power is released. A fraction of a second between keypress events is fine (enough for switch debouncing).

The Vol- button might be pressed the whole time, it does not matter if it is ever released, it just has to be pressed upon K3 reset. As I said before, I think I'd just tape it down when timing is unclear.

It also seems I had installed two drivers that came with ATK: the MX35 one plus the "windriver", by running "wd_install_4NT.bat". Not sure if both are needed, but I think the latter might provide functions for the other one.

I would certainly not risk a K3 that is "in production use" and not broken :-)

It always installs both drivers, even if you do not run the .bat. Upon reset the windriver one remains connected, only the iMX35 gets disconnected.
One thing what would interest me...might it be possible to go through the serial port using ATK ?

@WoenK,
ATK worked flawlessly the very first time with my working K3. I couldn't get it to work at all with the bricked one. I was getting the same error from the screenshot in page 5. Were you? I came to two conclusions. One was that the battery wasn't charging, but I charged mine for nearly two whole days on AC and I still got the error. I didn't bother with the swap but you tested that. The other conclusion was that the mmc was totally fried. I never got around to building a serial cable to check any output from uboot. You see no output at all which supports the totally fried mmc conclusion. I boxed mine up and sent it back to the mother ship yesterday.

There is more than one part inside of the SoC.
"Fried" is a figure of speech not a technical description.

If you need to know exactly what failed, use the eJTAG port (its marked on the K3 board).

It is possible for a single transistor to fail (out of many millions), which may cause occasional transient glitches, or massive failure, or anywhere in between. The USB enumeration circuits may be intact, but something needed to boot from mmc may have a hardware failure. Some intermittent failures can be thermal sensitive as well, so one diagnostic method is to cool chips with a non-conductive spray chiller during testing.

@WoenK,
ATK worked flawlessly the very first time with my working K3. I couldn't get it to work at all with the bricked one. I was getting the same error from the screenshot in page 5. Were you? I came to two conclusions. One was that the battery wasn't charging, but I charged mine for nearly two whole days on AC and I still got the error. I didn't bother with the swap but you tested that. The other conclusion was that the mmc was totally fried. I never got around to building a serial cable to check any output from uboot. You see no output at all which supports the totally fried mmc conclusion. I boxed mine up and sent it back to the mother ship yesterday.

geekmaster was right about the battery, it could be that it is not totally charged in the bricked on. Could be the the circuits controlling the charging got damaged.
Could be a lot of things
If it were some 80s electronics, I could fix it probably, but those tiny SMD thingies and the equipment you need to even find the error and the manuals to sip thorugh....way too much work. Mine was the leftover after a replacement so shipping it dows not help, I will keep it for spareparts

geekmaster was right about the battery, it could be that it is not totally charged in the bricked on. Could be the the circuits controlling the charging got damaged.
Could be a lot of things
If it were some 80s electronics, I could fix it probably, but those tiny SMD thingies and the equipment you need to even find the error and the manuals to sip thorugh....way too much work. Mine was the leftover after a replacement so shipping it dows not help, I will keep it for spareparts

You could temporarily swap batteries with a good kindle to try to charge it. That would tell you whether the problem is the battery or the charger circuit in the kindle. That is what I did to get one of my K4s working enough to debrick it when it would not charge at all. Of course, because the batteries are glued in, I had to place the two K4s back-to-back with cover removed to swap battery cables so the dead battery would charge.

Can someone please link me to to elaborate on what you can do if you can actually get your Kindle to hook up to ATK successfully? I'm unclear on what I should flash, and how I can use that to recover my Kindle.